1. Field of the Invention
This invention relates to game machines such as pachinko (pin-ball) game machines comprising a display device for displaying symbols necessary for playing games and a controller such as a microcomputer for controlling of a display.
2. Description of the Related Arts
For example, such a type of pachinko game machines is provided, as comprises a display device for displaying varying symbols when specified conditions are met, and a prize is given to a player when the varying display stops at a specified combination of symbols (a so-called big hit).
In such a game machine; the determination of a big hit or failure is made as follows: The count value of a counter is obtained adding a fixed number +1 repeatedly at specified counting time intervals and initialized (reset to zero) at constant periods, the count value is extracted at an appropriate timing, and it is determined whether or not the extracted count value falls within a specified range of a big hit. The timing of extracting the count value as a random number for determining the big hit is the timing at which a start command is issued for the start of the varying display by a startup win (entry of a game ball into a startup win hole, which will be described later).
While the above-described random number extraction process is carried out in the main circuit board in the game machine and every time the count value of the counter is renewed to the same value at constant periods, if a signal produced along with the renewal is issued outside, a present count value is easily known from outside. Therefore, the conventional count values can be used for deceit actions.
For example, there can be a deceit perpetrated in the following manner: A circuit board for a deceit purpose (a so-called xe2x80x9chang-on circuit boardxe2x80x9d) is connected to the main circuit board to tap signals outputted from the main circuit board and to constantly monitor the startup win detection signals. When a startup win signal is detected, the timing of extracting a count value for use as a random number for determining a big hit is delayed for the deceit purpose, the count value is extracted at a time point that can result in a big hit determination, and the count value is sent to the main circuit board to force the big hit determination to occur.
There are other manners of deceit using the xe2x80x9chang-on circuit boardxe2x80x9d: In one manner, a big hit is forced to occur by starting up a deceiving function using the xe2x80x9chang-on circuit boardxe2x80x9d according to a predetermined process including the connection of the hang-on circuit board to the main circuit board, and ejecting balls in a special manner. In another manner, the deceit function is started up by connecting a xe2x80x9chang-on circuit boardxe2x80x9d having wireless communication function to the main circuit board and by transmitting signals from a radio transmitter.
In another possible case, the game machine shop side may perpetrate the deceit, in which the deceit function is started up by wired or wireless remote control. In that case, the big hit is forcibly controlled not to occur so that the game shop side increases a profit by the deceit.
The object of the invention is to provide a game machine capable of preventing deceits by making it impossible to know easily from outside the renewal periods of the count value of the counter extracted as random numbers for determining big hits.
It is an object of the invention to provide a game machine comprising: a display device starting up a varying display in response to a specified startup command, the display device displaying symbols necessary for a game, the symbols including special symbols arranged so that the game state shifts to a special game state if the varying display stops at a specified state of combination of the special symbols; a controller executing a game control process including steps of controlling the varying display, the controller having a plurality of counters, count values of which are obtained from repeating additions of respective fixed numbers at respective specified counting time intervals and are initialized at respective constant periods, wherein a value calculated using the count values of two specified counters out of the plurality of counters, the respective constant periods of the two specified counters being different from each other, is extracted as a random number for a determination, when the startup command is issued, the determination being made whether or not the game state is to be shifted to the special game state on the basis of the random number.
With this invention, the calculated values using the count values of the two specified counters initialized at different periods when a varying display startup command is issued is extracted as a random number for making a special determination. Therefore, it does not happen that the same value as the random number for making a special determination such as a big hit determination is extracted at constant periods, and so it is difficult to know from outside the value that is extracted for use as the random number for making the special determination. This makes it possible to preclude the deceit perpetrated, for example, by connecting the xe2x80x9chang-on circuit board.xe2x80x9d
Another object of the invention is to provide a game machine in which the value calculated using the count values of the two specified counters is a sum of the count values of the two specified counters.
With this invention, a sum of the count values of the two specified counters is extracted as a random number, making the calculation easier.
Another object of the invention is to provideagame machine in which one of the two specified counters is a register for executing rewriting actions at specified rewriting time intervals. This register is generally called the refreshment register (R-register). The rewriting actions carried out with this register are indispensable for retaining data in dynamic type memories (DRAMs). The DRAM is a kind of memory means. This rewriting action is generally called the xe2x80x9crefreshment operation.xe2x80x9d
With this invention, while the above-described register is used for one of the two specified counters, since a DRAM accompanies an R-register, a new counter is unnecessary when a DRAM is used as memory means, making it economical.
Another object of the invention is to provideagame machine in which the controller executes the game control process every time an interruption signal is generated at specified interrupting time intervals, and one of the two specified counters is constituted to repeat the addition of the fixed number at the specified counting time intervals to obtain the count value which is initialized at the constant periods, after the execution of the game control process and until a next interruption signal is generated.
With this invention, one of the two specified counters is a counter that repeats adding a fixed number at the specified counting time intervals after the execution of the game control process and until the next interruption signal is produced and the counter is initialized at the constant periods. Therefore, the remaining time during which the occurrence of an interruption signal is waited for can be utilized effectively.
It is an object of the invention to provide a method of playing a game comprising the steps of; starting up a varying display in response to a specified startup command; displaying symbols necessary for the game, the symbols including special symbols arranged so that the game state shifts to a special game state if the varying display stops at a specified state of combination of the special symbols; and executing a game control process including the control of the varying display, the control process including, a first addition step of repeating a first addition of a first fixed number at first specified counting time intervals to obtain a first count value and storing the first count value, a first initializing step of initializing the first count value at first constant periods, a second addition step of repeating a second addition of a second fixed number at second specified counting time intervals to obtain a second count value and storing the second count value, a second initializing step of initializing the second count value at second constant periods different from the first constant periods, an extracting step of extracting a value calculated using the first and second count values as a special determination random number when the startup command is issued, and a determining step of determining if the game is to be shifted to the special game state on the basis of the special determination random number.
Another object of the invention is to provide a method of playing a game in which the value calculated using the first and second count values is a sum of the first and second count values.
Another object of the invention is to provide a method of playing a game comprising a refreshing step of generating refreshment pulses for executing rewriting actions at specified refreshing time intervals, wherein the addition step of repeating at least either one of the first and the second addition is performed at every generation of the refreshment pulse.
Another object of the invention is to provide a method of playing a game comprising a step of generating interruption signals at specified interrupting time intervals, wherein the game control process is performed every time the interruption signal is generated, and at least either one of the first and second addition is repeated at the specified counting time intervals after the game control process is performed until a next interruption signal is generated.